Did you experience a discharge when you shorted the anode of the CRT (step 5)? There is some debate amongst e.g. compact Mac owners (SE/30, ...) if this is necessary. A modern CRT should have bleeder resistors.

I did not hear a discharge, but I did let the monitor sit for a week just in case. I would think in terms of potential charge a 17" would probably be more dangerous than the 9" in a mac, but I'm not an expert by any means. I would say it's not worth the risk to skip this step.

My N4000A was completely dark, no more high voltage. Before, it already had had a distorted picture, but since I use my TurboStation only as a server, I didn't need the monitor and so I never fixed it. But now the NeXTStation would not boot any more and I needed to see what was written on the screen.

I took the list of capacitors and checked every one of them (for capacitance and ESR). And, oh boy, 20 of them were defective! I replaced only the defective ones, eh voila, I now have a perfect picture on the screen again! Thank you so much for hinting towards problems with the capacitors!!

I also added a switch to the monitor to turn it off (cuts +12V and -12V) when not needed. This way I hope to extend the life of the picture tube (and avoid the infamous dimming).

FYI here is the list of capacitors from my N4000A with comments (sorry for the German words in there):

I recently completed a recap job on my 4000A. The image seemed to be much more stable and crisp. However, mine, too has slightly dimmed. I adjusted the white level pot to compensate, but I'd be interested in giving rejuvenation a try. There are several B&K rejuvinators on eBay. Will any of them work?